File: hexloader.c

package info (click to toggle)
pd-hexloader 1.7-2
  • links: PTS, VCS
  • area: main
  • in suites: bullseye, buster, sid
  • size: 132 kB
  • sloc: ansic: 583; makefile: 389
file content (926 lines) | stat: -rw-r--r-- 23,794 bytes parent folder | download | duplicates (2)
1
2
3
4
5
6
7
8
9
10
11
12
13
14
15
16
17
18
19
20
21
22
23
24
25
26
27
28
29
30
31
32
33
34
35
36
37
38
39
40
41
42
43
44
45
46
47
48
49
50
51
52
53
54
55
56
57
58
59
60
61
62
63
64
65
66
67
68
69
70
71
72
73
74
75
76
77
78
79
80
81
82
83
84
85
86
87
88
89
90
91
92
93
94
95
96
97
98
99
100
101
102
103
104
105
106
107
108
109
110
111
112
113
114
115
116
117
118
119
120
121
122
123
124
125
126
127
128
129
130
131
132
133
134
135
136
137
138
139
140
141
142
143
144
145
146
147
148
149
150
151
152
153
154
155
156
157
158
159
160
161
162
163
164
165
166
167
168
169
170
171
172
173
174
175
176
177
178
179
180
181
182
183
184
185
186
187
188
189
190
191
192
193
194
195
196
197
198
199
200
201
202
203
204
205
206
207
208
209
210
211
212
213
214
215
216
217
218
219
220
221
222
223
224
225
226
227
228
229
230
231
232
233
234
235
236
237
238
239
240
241
242
243
244
245
246
247
248
249
250
251
252
253
254
255
256
257
258
259
260
261
262
263
264
265
266
267
268
269
270
271
272
273
274
275
276
277
278
279
280
281
282
283
284
285
286
287
288
289
290
291
292
293
294
295
296
297
298
299
300
301
302
303
304
305
306
307
308
309
310
311
312
313
314
315
316
317
318
319
320
321
322
323
324
325
326
327
328
329
330
331
332
333
334
335
336
337
338
339
340
341
342
343
344
345
346
347
348
349
350
351
352
353
354
355
356
357
358
359
360
361
362
363
364
365
366
367
368
369
370
371
372
373
374
375
376
377
378
379
380
381
382
383
384
385
386
387
388
389
390
391
392
393
394
395
396
397
398
399
400
401
402
403
404
405
406
407
408
409
410
411
412
413
414
415
416
417
418
419
420
421
422
423
424
425
426
427
428
429
430
431
432
433
434
435
436
437
438
439
440
441
442
443
444
445
446
447
448
449
450
451
452
453
454
455
456
457
458
459
460
461
462
463
464
465
466
467
468
469
470
471
472
473
474
475
476
477
478
479
480
481
482
483
484
485
486
487
488
489
490
491
492
493
494
495
496
497
498
499
500
501
502
503
504
505
506
507
508
509
510
511
512
513
514
515
516
517
518
519
520
521
522
523
524
525
526
527
528
529
530
531
532
533
534
535
536
537
538
539
540
541
542
543
544
545
546
547
548
549
550
551
552
553
554
555
556
557
558
559
560
561
562
563
564
565
566
567
568
569
570
571
572
573
574
575
576
577
578
579
580
581
582
583
584
585
586
587
588
589
590
591
592
593
594
595
596
597
598
599
600
601
602
603
604
605
606
607
608
609
610
611
612
613
614
615
616
617
618
619
620
621
622
623
624
625
626
627
628
629
630
631
632
633
634
635
636
637
638
639
640
641
642
643
644
645
646
647
648
649
650
651
652
653
654
655
656
657
658
659
660
661
662
663
664
665
666
667
668
669
670
671
672
673
674
675
676
677
678
679
680
681
682
683
684
685
686
687
688
689
690
691
692
693
694
695
696
697
698
699
700
701
702
703
704
705
706
707
708
709
710
711
712
713
714
715
716
717
718
719
720
721
722
723
724
725
726
727
728
729
730
731
732
733
734
735
736
737
738
739
740
741
742
743
744
745
746
747
748
749
750
751
752
753
754
755
756
757
758
759
760
761
762
763
764
765
766
767
768
769
770
771
772
773
774
775
776
777
778
779
780
781
782
783
784
785
786
787
788
789
790
791
792
793
794
795
796
797
798
799
800
801
802
803
804
805
806
807
808
809
810
811
812
813
814
815
816
817
818
819
820
821
822
823
824
825
826
827
828
829
830
831
832
833
834
835
836
837
838
839
840
841
842
843
844
845
846
847
848
849
850
851
852
853
854
855
856
857
858
859
860
861
862
863
864
865
866
867
868
869
870
871
872
873
874
875
876
877
878
879
880
881
882
883
884
885
886
887
888
889
890
891
892
893
894
895
896
897
898
899
900
901
902
903
904
905
906
907
908
909
910
911
912
913
914
915
916
917
918
919
920
921
922
923
924
925
926
/*
 * hexloader
 * Copyright (c) 2007-2009 IOhannes m zm�lnig @ IEM
 * For information on usage and redistribution, and for a DISCLAIMER OF ALL
 * WARRANTIES, see the file, "LICENSE.txt," that comes with Pd.  
 */

/*
 * this code adds an external "loader" to Miller S. Puckette's "pure data",
 * which allows the loading of libraries/externals with special characters
 * in the classname
 *
 * the infrastructure of this file is based on hcsteiner's "libdir" loader
 */


#ifdef __WIN32__
# define MSW
#endif

#include "m_pd.h"

#if (PD_MINOR_VERSION >= 40)

#if (PD_MINOR_VERSION < 42)
// with 0.42 the loader_t made it into s_stuff.h
# define MISSING_LOADER_T 1
#endif

#include "s_stuff.h"
#include "g_canvas.h"
#include <stdio.h>
#include <string.h>
#include <unistd.h>

#ifdef DL_OPEN
# include <dlfcn.h>
#endif
#ifdef UNISTD
# include <stdlib.h>
# include <unistd.h>
#endif
#ifdef _WIN32
# include <io.h>
# include <windows.h>
#endif
#ifdef __APPLE__
# include <mach-o/dyld.h> 
#endif


/* for now hexloading abstractions does not work very well, 
 * as it chokes when the hexloaded abstractions has nested abstractions
 * 
 * if you really want to enable hexloading patches, 
 * do so via the Makefile by defining HEXLOADER_PATCHES
 *
 */
//#define HEXLOADER_PATCHES

#ifdef HEXLOADER_PATCHES
void canvas_popabstraction(t_canvas *x);
static void*hexloader_fakenew(t_symbol *s, int argc, t_atom *argv);
t_pd pd_objectmaker;    /* factory for creating "object" boxes */
#endif

typedef struct _filepath
{
  t_symbol*filename;
  t_symbol*pathname;
} t_filepath;



typedef void (*t_hexloader_setup)(void);

#ifdef MISSING_LOADER_T
/* definitions taken from s_loader.c, since they weren't in header orignally */
typedef int (*loader_t)(t_canvas *canvas, char *classname);
void sys_register_loader(loader_t loader);
void class_set_extern_dir(t_symbol *s);
#endif

/* ==================================================== */

typedef struct _hexloader
{
  t_object x_obj;
} t_hexloader;
static t_class *hexloader_class;

static char *version = "1.7";


static char*hex_dllextent[] = {
#ifdef __FreeBSD__
  ".b_i386", ".pd_freebsd",
#endif
#ifdef __linux__
# ifdef __x86_64__
  ".l_ia64",
# else
  ".l_i386",
# endif
  ".pd_linux",
#endif /* linux */
#ifdef __APPLE__
# ifndef MACOSX3
  ".d_fat",
# else
  ".d_ppc",
# endif
  ".pd_darwin", 
#endif
#ifdef __WIN32__
  ".m_i386", ".dll",
#endif
  0}; /* zero-terminated list of extensions */



static  char *patch_extent[]={
  ".pd", 
  ".pat", 
  0};


/**
 * object-names containing non-alphanumerics like [||~]
 * can (sometimes) be not represented on filesystems (e.g.
 * "|" is a forbidden character) and more often they
 * cannot be used to construct a valid setup-function
 * ("||~_setup" or "||_tilde_setup" are really bad).
 * the way the "~" is handled, is non-generic and thus
 * sub-optimal.
 *
 * as a solution me and hcs proposed an encoding into
 * alphanumeric-values, using a hexadecimal representation
 * of all characters but [0-9A-Za-z_] (e.g. "+" is ascii
 * 43 and is thus represented by "0x2b" (hex-value all
 * lowercase and prepended with "0x")
 *
 * e.g. if we have a new class "mtx_||", pd first attempts
 * to find a file called "mtx_||.dll". if it succeeds, it
 * will try to call the "mtx_||_setup()" function.
 * if that fails we suggest to try and call a function
 * "setup_mtx_0x7c0x7c()" (the keyword setup is now at the
 * beginning of the function-name, in order to prevent the
 * names starting with numbers and in order to distinguish
 * between the normal setup-methods).
 * if no "mtx_||.dll" can be found, pd should then search
 * for a file "mtx_0x7c0x7c.dll" (guaranteed to be
 * representable on any filesystem); search this file for
 * the 2 setup-functions.
 * if all fails try to find "mtx_||.pd" and then
 * "mtx_0x7c0x7c.pd"
 */

/*
 * ideally this loader could somehow call the object-instantiator recursively
 * but with changed classnames;
 * this would allow us to use the hexloader stuff for all kinds of other loaders
 * including abstractions
 */


/* -------------------- utilities --------------------- */

/* --- symlist_t: a linked list of symbols --- */

/* linked list of loaders */
typedef struct symlist_ {
    t_symbol* sym;
    struct symlist_ *next;
} symlist_t;
static symlist_t*g_abstractionclasses=NULL;

static symlist_t*symlist_find(symlist_t*syms, t_symbol*sym) {
  symlist_t*dummy=syms;
  for(; dummy; dummy=dummy->next) {
    //    post("checking '%s' vs '%s'", sym, dummy->sym);
    if (sym==dummy->sym) {
      // we already have this entry!
      //      post("found sym %s=%s", sym, dummy->sym);
      return syms;
    }
  }
  return NULL;
}


static symlist_t*symlist_add(symlist_t*syms, t_symbol*sym) {
  symlist_t*dummy=syms;
  symlist_t*last=0;

  //  symlist_print("adder contained:", syms);

  if(NULL==sym)return syms;

  if(!dummy) {
    dummy=(symlist_t*)getbytes(sizeof(symlist_t));
    dummy->next=0;
    dummy->sym=sym;
    return dummy;
  }

  for(; dummy; dummy=dummy->next) {
    //    post("checking '%s' vs '%s'", sym, dummy->sym);
    if (sym==dummy->sym) {
      // we already have this entry!
      //      post("found sym %s=%s", sym, dummy->sym);
      return syms;
    }
    last=dummy;
  }
  dummy=last;

  dummy->next=(symlist_t*)getbytes(sizeof(symlist_t));
  dummy=dummy->next;
  dummy->next=0;
  dummy->sym=sym;

  //  symlist_print("adder contains::", syms);

  return syms;
}

/* --- namelist_t: a linked list of names --- */

/* linked list of loaders */
typedef struct namelist_ {
    char* name;
    struct namelist_ *next;
} namelist_t;

static void namelist_print(char*prefix, namelist_t*names) {
    for(; names; names=names->next) {
      if(prefix)startpost("%s:: ", prefix);
      post("%s",names->name);
    }
}

static namelist_t*namelist_add(namelist_t*names, char*name) {
  namelist_t*dummy=names;
  namelist_t*last=0;

  //  namelist_print("adder contained:", names);

  if(name==0)return names;

  if(!dummy) {
    dummy=(namelist_t*)getbytes(sizeof(namelist_t));
    dummy->next=0;
    dummy->name=name;
    return dummy;
  }

  for(; dummy; dummy=dummy->next) {
    //    post("checking '%s' vs '%s'", name, dummy->name);
    if (!strncmp(name, dummy->name, MAXPDSTRING)) {
      // we already have this entry!
      //      post("found name %s=%s", name, dummy->name);
      return names;
    }
    last=dummy;
  }
  dummy=last;

  dummy->next=(namelist_t*)getbytes(sizeof(namelist_t));
  dummy=dummy->next;
  dummy->next=0;
  dummy->name=name;

  //  namelist_print("adder contains::", names);

  return names;
}

static namelist_t*namelist_addlist(namelist_t*names, namelist_t*nl) {
  namelist_t*dummy=0;
  if(nl==0)return names;
  if(!names)return nl;

  /* try to add each entry in nl */
  for(dummy=nl; dummy->next; dummy=dummy->next) {
    names=namelist_add(names, dummy->name);
  }

  return names;
}

static void namelist_clear(namelist_t*names) {
  namelist_t*dummy=0;

  while(names) {
    dummy=names->next;
    names->next=0;
    names->name=0; /* we dont care since the names are allocated in the symboltable anyhow */
    freebytes(names, sizeof(namelist_t));
    names=dummy;
  }
}

/* --- filelist_t: a linked list of filenames, each associated with a list of setupfunction names --- */

typedef struct filelist_ {
  char *name;
  namelist_t*setupfun;
  struct filelist_ *next;
} filelist_t;

static void filelist_print(char*prefix, filelist_t*files) {
  for(; files; files=files->next) {
    if(prefix)startpost("%s: ", prefix);
    post("%s",files->name);
    namelist_print("\t", files->setupfun);
  }
}

static filelist_t*filelist_add(filelist_t*files, char*name, namelist_t*setupfun) {
  filelist_t *last=0, *dummy=files;
  if(name==0)return files;

  if(!dummy) {
    dummy=(filelist_t*)getbytes(sizeof(filelist_t));
    dummy->next=0;
    dummy->name=name;
    dummy->setupfun=namelist_addlist(0, setupfun);
    return dummy;
  }

  for(; dummy; dummy=dummy->next) {
    if (!strncmp(name, dummy->name, MAXPDSTRING)) {
      // we already have this entry!
      /* add additional setup-functions to this name */
      dummy->setupfun=namelist_addlist(dummy->setupfun, setupfun);
      return files;
    }
    last=dummy;
  }
  dummy=last;

  /* this is a new entry, add it to the list */

  dummy->next=(filelist_t*)getbytes(sizeof(filelist_t));
  dummy=dummy->next;
  dummy->next=0;
  dummy->name=name;
  dummy->setupfun=namelist_addlist(0, setupfun);

  return files;
}

static filelist_t*filelist_addlist(filelist_t*files, filelist_t*nl) {
  filelist_t*dummy=0;
  if(nl==0)return files;
  if(!files)return nl;

  /* try to add each entry in nl */
  for(dummy=nl; dummy->next; dummy=dummy->next) {
    files=filelist_add(files, dummy->name, dummy->setupfun);
  }

  return files;
}

static void filelist_clear(filelist_t*files) {
  filelist_t*dummy=0;

  while(files) {
    dummy=files->next;
    namelist_clear(files->setupfun);
    files->setupfun=0;
    files->name=0; /* we dont care since the files are allocated in the symboltable anyhow */
    files->next=0;
    freebytes(files, sizeof(filelist_t));
    files=dummy;
  }
}



/* ---------------- normalize names ------------------- */


/**
 * replace everything but [a-zA-Z0-9_] by "0x%x" 
 * @return the normalized version of org
 */
static char*hexloader_normalize(char*org, int skipslash)
{
  char*orgname=org;
  char altname[MAXPDSTRING];
  t_symbol*s=0;

  int count=0;
  int i=0;

  for(i=0; i<MAXPDSTRING; i++)
    altname[i]=0;

  i=0;
  while(*orgname && i<MAXPDSTRING)
    {
      char c=*orgname;
      if((c>='0' && c<='9')|| /* [0-9] */
         (c>='A' && c<='Z')|| /* [A-Z] */
         (c>='a' && c<='z')||/* [a-z] */
         (c=='_') ||        /* [_] */
         (skipslash && c=='/')
         )
        {
          altname[i]=c;
          i++;
        }
      else /* a "bad" character */
        {
          sprintf(altname+i, "0x%02x", c);
          i+=4;
          count++;
        }
      orgname++;
    }

  s=gensym(altname);
  //  post("normalize=%s", s->s_name);
  return s->s_name;
}

/**
 * replace only / \ : * ? " < > | by 0x%x since these are forbidden on some filesystems
 * @return the normalized version of org
 */
static char*hexloader_fsnormalize(char*org)
{
  char*orgname=org;
  char altname[MAXPDSTRING];
  t_symbol*s=0;

  char forbiddenchars[]={ 
    //    '/', '\\', ':', '*', '?', '"', '<', '>', '|',
    '\\', ':', '*', '?', '"', '<', '>', '|',
    0};

  int count=0;
  int i=0;

  for(i=0; i<MAXPDSTRING; i++)
    altname[i]=0;

  i=0;
  while(*orgname && i<MAXPDSTRING)
    {
      char c=*orgname;
      char*forbidden=forbiddenchars;
      int found=0;

      while(*forbidden) {
        if(c==*forbidden) {
          sprintf(altname+i, "0x%02x", c);
          i+=4;
          count++;
          found=1;
          break;
        }
        forbidden++;
      }
      if(!found)
        {
          altname[i]=c;
          i++;
        }
      orgname++;      
    }

  s=gensym(altname);
  //  post("fsnormalize=%s", s->s_name);
  return s->s_name;
}


static filelist_t*hexloader_deslashify(filelist_t*names, char*prefix, char*postfix) {
  filelist_t*result=names;
  int i=0;
  char*cp=0;
  char buf[MAXPDSTRING];
  t_symbol*s;

  snprintf(buf, MAXPDSTRING, "%s%s", prefix, postfix);
  s=gensym(buf);

  result=filelist_add(result, s->s_name, 0);

  for(cp=postfix; *cp; cp++) {
    if(*cp=='/') {
      char *postfix2=postfix+i+1;
      char buf2[MAXPDSTRING];

      snprintf(buf2, MAXPDSTRING, "%s", prefix);
      strncat(buf2, postfix, i);
      strcat(buf2, "/");
      result=hexloader_deslashify(result, buf2, postfix2);

      snprintf(buf2, MAXPDSTRING, "%s", prefix);
      strncat(buf2, postfix, i);
      strcat(buf2, "0x2f");
      result=hexloader_deslashify(result, buf2, postfix2);

    }
    i++;
  }

  return result;
}


static namelist_t*hexloader_fsnormalize_list(namelist_t*names, char*org) {
  char*simple=hexloader_fsnormalize(org);
  names=namelist_add(names, org);
  names=namelist_add(names, simple);

  return names;
}



/* ---------------- core code ------------------- */

static namelist_t*hexloader_getaltsetups(namelist_t*names, char*name) {
  char sbuf[MAXPDSTRING];
  t_symbol*s;
  snprintf(sbuf, MAXPDSTRING, "%s_setup", name);
  s=gensym(sbuf);
  names=namelist_add(names, s->s_name);
  snprintf(sbuf, MAXPDSTRING, "setup_%s", name);
  s=gensym(sbuf);
  names=namelist_add(names, s->s_name);
  return names;
}
static namelist_t*hexloader_getaltsetup(namelist_t*names, char*name) {
  namelist_t*result=names;
  char*strippedname=name;
  char*cp=name;

  while(*cp++) {
    if(*cp=='/'){
      strippedname=cp+1;
    }
  }
 
  result=hexloader_getaltsetups(result, strippedname);
  result=hexloader_getaltsetups(result, hexloader_normalize(strippedname, 0));
  //  post("added to %s\n", name);
  return result;
}

static filelist_t*hexloader_fillaltsetupfuns(filelist_t*files) {
  filelist_t*f;
  for(f=files; f; f=f->next) {
    f->setupfun=namelist_addlist(f->setupfun, hexloader_getaltsetup(f->setupfun, f->name));
  }
  return files;
}

/**
 * @return a 0-terminated array of all filenames we consider to be alternative names and associated setup-functions
 */

static filelist_t*hexloader_getalternatives(char*org) {
  filelist_t*files=0;

  files=filelist_add(files, org, 0);
  files=filelist_add(files, hexloader_fsnormalize(org), 0);
  files=filelist_add(files, hexloader_normalize(org, 1),0);
  files=filelist_add(files, hexloader_normalize(org, 0),0);
  files=hexloader_deslashify(files, "", org);

  hexloader_fillaltsetupfuns(files);
  //  filelist_print("ALTER: ", files);

  return files;
}

static int hexloader_doload(char*filename, char*setupfun) {
    t_hexloader_setup makeout=0;

#ifdef DL_OPEN
    void *dlobj = dlopen(filename, RTLD_NOW | RTLD_GLOBAL);
    if (!dlobj)
    {
      verbose(2, "%s: %s", filename, dlerror());
      class_set_extern_dir(&s_);
      return (0);
    }
    makeout = (t_hexloader_setup)dlsym(dlobj,  setupfun);
#elif defined __WIN32__
    HINSTANCE ntdll;
    sys_bashfilename(filename, filename);
    ntdll = LoadLibrary(filename);
    if (!ntdll)
    {
      verbose(2, "%s: couldn't load", filename);
      class_set_extern_dir(&s_);
      return (0);
    }
    makeout = (t_hexloader_setup)GetProcAddress(ntdll, setupfun);  
#else
    error("alas! somebody (you?) has compiled [hexloader] without support for loading externals...how should i load?");
#endif

    if (!makeout)
    {
      verbose(2, "hexload object: Symbol \"%s\" not found", setupfun);
      class_set_extern_dir(&s_);
      return 0;
    }
    (*makeout)();
    return (1);
}

/**
 * open a file (given via pathname+filename) as dll and call various
 * setupfunctions (as can be calculated from the altnames array
 * @param pathname the path of the file
 * @param filename the name (without path) of the file
 * @param altnames a zero-terminated array of possible non-generic parts of the setup-function
 * @return 1 on success, 0 otherwise
 */
static int hexloader_loadfile(char*pathname, char*filename, namelist_t*altnames) 
{
  char setupfun[MAXPDSTRING];
  char fullfile[MAXPDSTRING];
  namelist_t*altname=altnames;

  sprintf(fullfile, "%s/%s", pathname, filename);

  while(altname) {
    verbose(0, "hexloader trying %s (%s)", fullfile, altname->name);
    if(hexloader_doload(fullfile, altname->name))
      return 1;

    altname=altname->next;
  }

  return 0;
}



/**
 * try to open a file (given via pathname+filename) as a patcher
 * TODO: make this work....
 * @param pathname the path of the file
 * @param filename the name (without path) of the file
 * @param altclassname the alternative classname we currently use...
 * @return 1 on success, 0 otherwise
 */


/* this only gets called if we have already found an abstraction-file */
static t_filepath*hexloader_loadpatch(char*pathname, char*filename, char*altclassname, char*realclassname)
{
  char fullfile[MAXPDSTRING];
  t_symbol*realname=gensym(realclassname);
  t_filepath*result=NULL;
  sprintf(fullfile, "%s/%s", pathname, filename);

#ifdef HEXLOADER_PATCHES
  if(symlist_find(g_abstractionclasses, realname)) {
    // already in the list
  } else {
    class_addcreator((t_newmethod)hexloader_fakenew, realname, A_GIMME, 0);
    g_abstractionclasses=symlist_add(g_abstractionclasses, realname);
  }

  result=getbytes(sizeof(t_filepath));
  result->filename=gensym(filename);
  result->pathname=gensym(pathname);

  
#else
  error("BUG: hexloader not loading abstraction: %s (not yet implemented)", fullfile);
#endif /* HEXLOADER_PATCHES */
  return result;
}
/**
 * the actual loader:
 *  example-nomenclature:
 *   "class": the original class-name (e.g. containing weird characters)
 *   "CLASS": the normalized class-name (with all weirdness replaced by hex-representations
 *   "ext"  : the external-extension (e.g. "dll" or "pd_linux" or...)
 *  example:
 *   trying to create an object [class] (and pd fails for whatever reasons, and thus callsus)
 *   - search for a file "class.ext" in our search-path
 *    + if found
 *     try to call "class_setup()" function 
 *     if fails, try to call "setup_CLASS()" function
 *    (if fails, try to call "CLASS_setup()" function)
 *    - "class.ext" file not found
 *   - search for a file "CLASS.ext" in our search-path
 *    + if found
 *     try to call "class_setup()" function 
 *     if fails, try to call "setup_CLASS()" function
 *    (if fails, try to call "CLASS_setup()" function)
 *   - if everything fails, return...
 *
 * @param canvas the context of the object to be created
 * @param classname the name of the object (external, library) to be created
 * @return 1 on success, 0 on failure
 */

static int hexloader_trylibraries(t_canvas*x, filelist_t*altnames0) {
  int fd = -1;
  char dirbuf[MAXPDSTRING];
  char*nameptr;
  filelist_t*altnames=altnames0;
  
  /* try binaries */
  while(altnames) {
    char*altname=altnames->name;
    int dll_index=0;
    char*dllextent=hex_dllextent[dll_index];
    while(dllextent!=0) {
      if(NULL!=x)
        fd=canvas_open(x, altname, dllextent, dirbuf, &nameptr, MAXPDSTRING, 0);
      else
        fd = open_via_path(".", altname, dllextent, dirbuf, &nameptr, MAXPDSTRING, 0);

      if (fd >= 0) {
        close (fd);

        if(hexloader_loadfile(dirbuf, nameptr, altnames->setupfun)) {
          return 1;
        }
      }
      dll_index++;
      dllextent=hex_dllextent[dll_index];
    }

    altnames=altnames->next;
  }

  return 0;
}
static t_filepath*hexloader_trypatches(t_canvas*x, filelist_t*altnames0, char*classname) {
  int fd = -1;
  char dirbuf[MAXPDSTRING];
  char*nameptr;
  filelist_t*altnames=altnames0;

  /* try patches */
  altnames=altnames0;
  while(altnames) {
    char*altname=altnames->name;
    int extindex=0;
    char*extent=patch_extent[extindex];
    if(strcmp(altname, classname)) { /* we only try if it is worth trying... */
      while(extent!=0) {
        if(NULL!=x)
          fd=canvas_open(x, altname, extent, dirbuf, &nameptr, MAXPDSTRING, 0);
        else
          fd = open_via_path(".", altname, extent, dirbuf, &nameptr, MAXPDSTRING, 0);
        if (fd >= 0) {
          close (fd);
          t_filepath*fp=hexloader_loadpatch(dirbuf, nameptr, altname, classname);
          if(fp) {
            return fp;
          }
        }
        extindex++;
        extent=patch_extent[extindex];
      }
    }
    altnames=altnames->next;
  }

  return 0;
}


/**
 * this is the actual loader:
 * we first try to load an external with alternative (hexified) names
 * if this fails, we fall back to load a patch with these names
 */
static int hexloader_doloader(t_canvas *canvas, filelist_t*altnames0, char*classname)
{
  t_filepath*fp=0;
  if(hexloader_trylibraries(canvas, altnames0))
    return 1;

  fp=hexloader_trypatches(canvas, altnames0, classname);
  if(fp) {
    freebytes(fp, sizeof(t_filepath));
    return 1;
  }

  return 0;
}

/**
 * recursive use of our powers:
 * try to load the object with alternative (hexified) names using other available loaders
 * when it comes to us, we just return 0...
 */
static int hexloader_callothers(t_canvas *canvas, filelist_t*altnames) {
  int result=0;
  while(altnames) {
    char*altname=altnames->name;
    verbose(2, "calling sys_load with '%s'", altname);
    result=sys_load_lib(canvas, altname);
    if(result==1) {
      return 1;
    }
    altnames=altnames->next;
  }
  return 0;
}


/**
 * the loader
 *
 * @param canvas the context of the object to be created
 * @param classname the name of the object (external, library) to be created
 * @return 1 on success, 0 on failure
 */
static int hexloader_loader(t_canvas *canvas, char *classname)
{
  filelist_t*altnames=0;
  int result=0;

  static int already_loading=0;
  if(already_loading)return 0;
  already_loading=1;

  /* get alternatives */
  altnames=hexloader_getalternatives(classname);

  /* try other loaders with our power */
  if(result==0){
    result=hexloader_callothers(canvas, altnames);
  }

  /* do the loading ourselves */
  if(result==0) {
    result=hexloader_doloader(canvas, altnames, classname);
  }

  /* clean up */
  filelist_clear(altnames); 

  already_loading=0;
  return result;
}

#ifdef HEXLOADER_PATCHES
static void*hexloader_fakenew(t_symbol*s, int argc, t_atom*argv) {
  t_pd*current = s__X.s_thing;
  t_filepath*fp=0;
  filelist_t*altnames=0;

  verbose(1, "hexloader: disguising as '%s'", s->s_name);

  if(!pd_objectmaker) {
    error("BUG: no pd_objectmaker found");
    return 0;
  }

  /* get alternatives */
  altnames=hexloader_getalternatives(s->s_name);
  /* do the loading */
  fp=hexloader_trypatches(NULL, altnames, s->s_name);
  /* clean up */
  filelist_clear(altnames); 

  if(fp) {
    canvas_setargs(argc, argv);
    /* this fails when the object is loaded the first time
     * since m_class.c:new_anything() has set the "tryingalready" flag
     * the next time the object is created, it will work, since pd_objectmaker already knows about us and thus new_anything() never get's called
     */
    /* ideas how to fix this:
     * - a simple hack is to register the abstractions to be hexloaded beforehand (but we have to know them before they are requested!)
     * - override the anything-method of pd_objectmaker "new_anything()" and call it ourselves (this makes the entire sys_loader hook absurd)
     *
     * claude's "abstraction caching" (http://lists.puredata.info/pipermail/pd-dev/2008-10/012334.html) works because he is injecting the code right
     * before sys_load_lib() and the "tryingalready" guards
     */
    binbuf_evalfile(fp->filename, fp->pathname);
    freebytes(fp, sizeof(t_filepath));
    if (s__X.s_thing != current)
      canvas_popabstraction((t_canvas *)(s__X.s_thing));
    canvas_setargs(0, 0);
    return pd_newest();
  } else 
    return 0;
}
#endif /* HEXLOADER_PATCHES */

#endif /* PD_MINOR_VERSION>=40 */


static void*hexloader_new(t_symbol *s, int argc, t_atom *argv)
{
  t_hexloader*x = (t_hexloader*)pd_new(hexloader_class);
  return (x);
}

void hexloader_setup(void)
{
  /* relies on t.grill's loader functionality, fully added in 0.40 */
  post("hexloader %s",version);  
  post("\twritten by IOhannes m zm�lnig, IEM <zmoelnig@iem.at>");
  post("\tcompiled on "__DATE__" at "__TIME__ " ");
  post("\tcompiled against Pd version %d.%d.%d.%s", PD_MAJOR_VERSION, PD_MINOR_VERSION, PD_BUGFIX_VERSION, PD_TEST_VERSION);

#if (PD_MINOR_VERSION >= 40)
  sys_register_loader(hexloader_loader);
#else
  error("to function, this needs to be compiled against Pd 0.40 or higher,\n");
  error("\tor a version that has sys_register_loader()");
#endif

  hexloader_class = class_new(gensym("hexloader"), (t_newmethod)hexloader_new, 0, sizeof(t_hexloader), CLASS_NOINLET, A_GIMME, 0);
}